[TD]spelling in comments

src/Mod/TechDraw/App/DrawPage.cpp

@@ -381,7 +381,7 @@ void DrawPage::unsetupObject()
         const std::vector<App::DocumentObject*> currViews = Views.getValues();
         for (auto& v : currViews) {
             //NOTE: the order of objects in Page.Views does not reflect the object hierarchy
-            //      this means that a ProjGroup could be deleted before it's child ProjGroupItems.
+            //      this means that a ProjGroup could be deleted before its child ProjGroupItems.
             //      this causes problems when removing objects from document
             if (v->isAttachedToDocument()) {
                 std::string viewName = v->getNameInDocument();

src/Mod/TechDraw/App/DrawUtil.cpp

@@ -935,7 +935,7 @@ QPointF DrawUtil::invertY(QPointF v)
     return QPointF(v.x(), -v.y());
 }
 
-//! convert a gui point into it's app space equivalent.  this requires us to
+//! convert a gui point into its app space equivalent.  this requires us to
 //! perform the invert, scale, rotate operations in the reverse order from
 //! that used to generate the qt point.
 //! Note: the centering operation is not considered here

src/Mod/TechDraw/App/ShapeUtils.cpp

@@ -265,7 +265,7 @@ TopoDS_Shape ShapeUtils::mirrorShape(const TopoDS_Shape& input, const gp_Pnt& in
         return transShape;
     }
     try {
-        // Make tempTransform scale the object around it's centre point and
+        // Make tempTransform scale the object around its centre point and
         // mirror about the Y axis
         gp_Trsf tempTransform;
         //BRepBuilderAPI_Transform will loop forever if asked to use 0.0 as scale

src/Mod/TechDraw/App/TechDrawExport.cpp

@@ -285,7 +285,7 @@ void SVGOutput::printBezier(const BRepAdaptor_Curve& c, int id, std::ostream& ou
         Handle(Geom_BezierCurve) bezier = c.Bezier();
         Standard_Integer poles = bezier->NbPoles();
 
-        // if it's a bezier with degree higher than 3 convert it into a B-spline
+        // if its a bezier with degree higher than 3 convert it into a B-spline
         if (bezier->Degree() > 3 || bezier->IsRational()) {
             TopoDS_Edge edge = asBSpline(c, 3);
             if (!edge.IsNull()) {